Stargardt disease

What is Stargardt disease?

Stargardt disease (also known as Stargardt’s or Stargardt Syndrome) is a rare genetic eye condition that affects the macula – the part of the eye’s retina responsible for sharp, detailed central vision. Stargardt disease typically begins in childhood or adolescence, often presenting between the ages of six and twenty years old. The genetic mutations that cause the condition are present from birth. Stargardt disease causes gradual loss of central vision due to a build-up of fatty deposits called lipofuscin in the retina. These deposits damage the light sensitive cells responsible for clear, detailed vision.

Symptoms

The early symptoms of Stargardt disease can overlap with many common vision problems, making it a rare but important consideration. These signs include:

• Blurred or distorted vision: Difficulty seeing fine details, reading, or recognising faces.
• Dark or blank spots: Small areas of central vision may appear dim or missing.
• Light sensitivity: Discomfort in bright light or glare.
• Trouble in low light: Difficulty adjusting to dim environments.
• Colour changes: Colours may appear dull or harder to distinguish.

In young people

While Stargardt disease is uncommon, it can sometimes be spotted in children through behaviours like:

• Holding objects close to their face or squinting to see.
• Struggling with reading, recognising faces, or seeing the board at school.
• Avoiding visually demanding tasks or appearing clumsy due to impaired depth perception.

These symptoms are more often linked to less serious vision issues but should still prompt a visit to an eye care practitioner for a thorough evaluation if they occur. Early detection, regardless of the cause, is key to better outcomes.

Stargardt disease typically progresses over time, but the rate and severity can vary widely between individuals. Some people experience slow progression with relatively stable vision for many years, while others may notice a more rapid decline in central vision.

Stargardt disease does not always reach an advanced stage, but if it progresses significantly, difficulty recognising faces and performing other tasks that rely on central vision may become more pronounced. Early diagnosis and management, such as protecting the eyes from bright light and UV exposure, can help slow progression in some cases.

More advanced symptoms can include:

• Blurred or distorted central vision.
• Difficulty reading or recognising faces.
• Loss of colour vision in advanced stages.
• Peripheral vision is typically preserved but may be reduced in severe cases.

Causes and risk factors

Stargardt disease is usually caused by mutations in the ABCA4 gene, which affects the ability of retinal cells to process vitamin A. This leads to the accumulation of toxic byproducts in the retina, damaging the macula over time. Less commonly, it can involve mutations in other genes.

Stargardt disease is a genetically inherited condition. It is inherited in an autosomal recessive pattern, meaning a person must inherit two copies of the mutated gene (one from each parent) to develop the condition. Parents are typically carriers, showing no symptoms themselves.

If both parents are carriers, each child has:

• 25 percent chance the child will have the disease. 
• 50 percent chance the child will be a carrier. 
• 25 percent chance the child will inherit no altered genes.

In rare cases, Stargardt disease can be autosomal dominant, requiring only one altered gene to cause the condition. Genetic counselling can provide more clarity on risks.

Risk factors include:

• Having two copies of a mutated ABCA4 gene.
• A family history of Stargardt disease.
• Prolonged exposure to bright light or UV rays, which may accelerate retinal damage, and potentially increase the risk of Stargardt disease progressing.

Diagnosis

Stargardt disease is diagnosed by an eyecare professional through a combination of eye exams, retinal imaging and genetic testing to confirm ABCA4 gene mutations.

• Eye exams: Using fundus photography (capturing detailed images of the retina), doctors can see characteristic yellowish flecks (lipofuscin) in the retina.
• Optical coherence tomography (OCT): A non-invasive imaging test to analyse retinal structure. Learn more about OCT scans.
• Fluorescein angiography: To examine blood flow in the retina.
• Genetic testing: Confirms the diagnosis and identifies the causative gene mutation.
• Visual field test: Monitors the progression of the condition. Learn more about visual field tests.

Treatment

There is currently no cure for Stargardt disease, but treatments focus on slowing progression and managing symptoms. Regular monitoring by an eyecare professional is essential for managing this condition. Management may include:

• Protecting the eyes: Wearing sunglasses to reduce UV and blue light exposure.
• Low vision aids: Using magnifiers, screen readers, or other assistive devices.
• Lifestyle adjustments: Avoiding smoking and maintaining overall eye health.
• Orientation and mobility training: Learning strategies to maintain independence in daily activities and improve navigation skills.

For more information

More information can be found at Macular Disease Foundation Australia.

Visit your doctor or eye care professional for expert advice and guidance on your eye health.